There are many ways to write this code. One of those ways is with grep. You could make a foreach loop to do the same thing.

#!/usr/bin/perl -w 
use strict;

my @array = (2,4,7,5,8);

# grep would return indicies of all 7's
# here, just the first one is all we keep track of

my ($first_seven) = grep{$array[$_] == 7}(0..@array-1);

print $first_seven;  # prints 2
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